Netcache by Netapp does all this quite well. Pricey but really good on this stuff,

They have various models based on throughput and cache (disk) capacity

http://www.netapp.com/products/netcache/

Raymond

From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Jon Lyons
Sent: Thursday, April 06, 2006 8:04 PM
To: nanog@merit.edu
Subject: Proxy/Caching Servers

Hey all,

I need some recommendations on proxy servers for enterprise environments. Our current product can't handle the load & is no longer being supported by the vendor. The devices need to handle at least 1000+ concurrent connections at about 20 Mbit/s. Websites, Streaming, etc, etcâ€¦

Not sure if there's one product that does what I'm looking for:

1. Appliance based (preferred, but not required)
2. Clusterable/VRRP Setup or can be used behind a load balancer
3. Web/FTP virus checking
4. Caching
5. Web content filtering (include ability to add manually to a deny list)
6. Logging and user auditing (via name or client IP address)
7. Real-time traffic monitoring
8. Grant/Deny access to particular websites from individual/grouped client IP addresses

Thanks

Yahoo! Messenger with Voice. PC-to-Phone calls for ridiculously low rates.